1. Field Of The Invention
Sensitizers comprising .alpha.,.beta.-unsaturated ketones derived from acetyltetrahydronaphthalene or acetylindane and dialkylaminoaryl aldehydes; and photopolymerizable compositions comprising said sensitizers.
2. Description Of The Prior Art
Use of sensitizers to extend the photosensitivity of photopolymerizable compositions into the visible region of the spectrum and to increase the speed of polymerization is known. Baum et al, U.S. Pat. No. 3,652,275, disclose selected bis(p-dialkylaminobenzylidene) ketones as sensitizers to enhance the efficiency of hexaarylbiimidazole initiator systems in photopolymerizable compositions.
Dueber, U.S. Pat. No. 4,162,162, discloses photopolymerizable compositions comprising a photopolymerizable monomer, a hexaarylbiimidazole initiator, and a sensitizing amount of a compound derived from aryl ketones and p-dialkylaminoaryl aldehydes. Alkyl-substituted 1-phenyl-2-propen-1-ones are disclosed, and a methylenedioxy heterocyclic-substituted 1-phenyl-2-propen-1-one is exemplified (Example 21). There is no disclosure of a carbocyclic-substituted 1-phenyl-2-propen-1-one.
Hartman et al, U.S. Pat. No. 3,617,288, disclose the use of substituted 2-propen-1-ones as sensitizers for photolyzable organic halogen compounds. The sensitizers are free of amine groups more basic than the diphenylamino radical.
Schlesinger et al, U.S. Pat. No. 3,257,202, disclose polymerization products of olefinic ketones as photoconductor coatings for electrophotographic purposes. Certain 1-phenyl-2-propen-1-ones are disclosed, but there is no disclosure of a carbocyclic-substituted 1-phenyl-2-propen-1-one.